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schwit1 writes: "The Arecibo radio telescope has confirmed the existence of fast radio pulses. "Fast radio bursts (FRBs) are bright flashes of radio waves that last only a few thousandths of a second. Scientists using the Parkes Observatory in Australia recorded such events for the first time, but the lack of any similar findings by other facilities led to speculation that the Australian instrument might have been picking up signals originating from sources on or near Earth. The discovery at Arecibo is the first detection of a fast radio burst using an instrument other than the Parkes radio telescope. The position of the radio burst is in the direction of the constellation Auriga in the Northern sky.

"Our result is important because it eliminates any doubt that these radio bursts are truly of cosmic origin," continues Victoria Kaspi, an astrophysics professor at McGill University in Montreal and Principal Investigator for the pulsar-survey project that detected this fast radio burst. "The radio waves show every sign of having come from far outside our galaxy – a really exciting prospect." Exactly what may be causing such radio bursts represents a major new enigma for astrophysicists. Possibilities include a range of exotic astrophysical objects, such as evaporating black holes, mergers of neutron stars, or flares from magnetars — a type of neutron star with extremely powerful magnetic fields." Be warned: All of the above theories could also be wrong. These fast radio flashes could just as easily turn out to be something entirely unpredicted.

I thank you for your wisdom, but it's entirely not relevant to above discussion.

While the Equivalence Principle may very well be an approximation (Can has Quantum Gravity?), it is more accurate a model than we have technology to either disprove, or even imply that it is likely to be in question. I'm pretty sure he was talking about the Cosmological Principle, which is actually a questionable axiom, that simply has a few pieces of observational evidence in support of it, and plenty of evidence that c

It's worth pointing out that a good way to send a signal would be to have a bright but transient beacon, which doesn't itself transmit information (other than "here I am"), but serves to tell others where to point their high-gain radiotelescopes.

This could be what such a beacon would look like.

Not to mention the power output it would need to send a detectible signal from another galaxy.

From the summary: "bright flashes of radio waves that last only a few thousandths of a second.

A high power for a few milliseconds may not take an enormous amount of energy.

Unfortunately, we didn't have any openings for reactionless engine technicians or 4th order energy engineers.

You misunderstood. It was the aliens looking for cheap human labor that could be exploited. I mean, you go all the way to Alma Crematoria to take a job and it turns out you're becoming an indentured servant, what are you gonna do? Are you going to be able to afford a ticket back to the Earth? You think you'll find another job there, without good language skills and a degree from an Alma Crematorium university? You may wind up picking cabbage... or working at Walmart. By the time you get there they'll have

And hook up a TV and big speakers to isolate the signal. Then once we decode it, we can transport a volunteer to the alien planet. Though, we should build two, just in case a religious terrorist blows one up. If we do this carefully, with Small moves, it's possible. Small moves.

And hook up a TV and big speakers to isolate the signal. Then once we decode it, we can transport a volunteer to the alien planet. Though, we should build two, just in case a religious terrorist blows one up. If we do this carefully, with Small moves, it's possible. Small moves.

If you're going to channel "Contact" at least use the novel instead of the movie. The novel was enormously better. Not that that says much, as the movie was awful.

Please tell me the novel doesn't wreck the ending in some weird appeasement to religion like the movie did.

Not as I recall. There were other things that the movie ruined too. It's an okay novel, I wouldn't buy a hardcover it's not worth that, but the mass market paperback would certainly be cheap enough to make it worthwhile to read.

An extragalactic origin, if correct, would put the source likely millions of light years away. An artificial radio source detectable over that distance would take a truly phenomenal amount of power, on par with stellar events like supernovae or black hole mergers. Or it would need to be very narrowly beamed, in which case how does ET know to point in our direction?

Bear in mind that the entire RF output of our planet (radio waves streaming into space) would not be detectable by Arecibo even 10 light years aw

It is a very narrow beam, but they don't point it in our direction. Imagine a then wedge of laser/maser, etc. light being broadcast outward radially on a continuous basis. As the planet rotates, the wedge sweeps pretty much every angle. As you see the wedge only when it points directly at you, it appears to blink very rapidly

The summary doesn't mention extra terrestrials. Is this because they don't want to jump to conclusions or is it because the nature of the pulses doesn't appear to be organic?

When astronomers point a telescope at the sky and see a large bright object, they tend to assume it's a star, not a giant alien lighthouse. If they see a bright flash of light, they assume it's due to some natural process and not an alien strobe-light. Is there some reason they would jump to an "it's aliens" conclusion in this case? You do understand that light is light, right? Even if the wavelength puts it in the radio-frequencies instead of the visible-spectrum? There's no particular reason light in

Is there some reason they would jump to an "it's aliens" conclusion in this case?

It's in the wording of the article summery. Radio pulse sort of initially brings thoughts of a radio station receiver like in a car or home theater, a purpose constructed signal meant to convey messages. Add in the "might have been picking up signals originating from sources on or near Earth" and it kind of reinforces the sentiment of a constructed signal.

GP isn't the only one making that jump either. There are some posts abou

You get a radio pulse every time lightning strikes. I think that this is a fairly unlikely explanation. If it were more regular and had some kind of repeating pattern to it then I'd start thinking galactic navigation beacon or something, but natural pulsars probably work well enough for that already.

While fast radio bursts last just a few thousandths of a second and have rarely been detected, the new result confirms previous estimates that these strange cosmic bursts occur roughly 10,000 times a day over the whole sky.

That's a lot of aliens. Or maybe we are inside of a slow thinking alien's head.

While fast radio bursts last just a few thousandths of a second and have rarely been detected, the new result confirms previous estimates that these strange cosmic bursts occur roughly 10,000 times a day over the whole sky.

Yes, and I have a big problem with them being called "theories." They are at best hypotheses, and likely pure speculation. Scientists get mad when creationists say, "Oh, but you call it the THEORY of Evolution, that means it's not necessarily true!" and say creationists don't know the meaning of the word theory. Ok, then, use it correctly yourselves.

How difficult would it be to capture something like this? Couldn't a normal sensor sensitive to this wavelength capture this since the integration time is probably going to be longer than a few thousandths of a second?

As usual with astronomy articles, it can be found on the arXiv [arxiv.org], freely available to all. It goes into much more detail than the article linked in the summary. Here is the abstract:

Recent work has exploited pulsar survey data to identify temporally isolated, millisecond-duration radio bursts with large dispersion measures (DMs). These bursts have been interpreted as arising from a population of extragalactic sources, in which case they would provide unprecedented opportunities for probing the intergalactic medium; they may also be linked to new source classes. Until now, however, all so-called fast radio bursts (FRBs) have been detected with the Parkes radio telescope and its 13-beam receiver, casting some concern about the astrophysical nature of these signals. Here we present FRB 121102, the first FRB discovery from a geographic location other than Parkes. FRB 121102 was found in the Galactic anti-center region in the 1.4-GHz Pulsar ALFA survey with the Arecibo Observatory with a DM = 557.4 \pm 3 pc cm^{-3}, pulse width of 3\; \pm 0.5 ms, and no evidence of interstellar scattering. The observed delay of the signal arrival time with frequency agrees precisely with the expectation of dispersion through an ionized medium. Despite its low Galactic latitude (b = -0.2^{\circ}), the burst has three times the maximum Galactic DM expected along this particular line-of-sight, suggesting an extragalactic origin. A peculiar aspect of the signal is an inverted spectrum; we interpret this as a consequence of being detected in a sidelobe of the ALFA receiver. FRB 121102's brightness, duration, and the inferred event rate are all consistent with the properties of the previously detected Parkes bursts.